Grandstream GS-GXP2135 Enterprise IP Phone with Gigabit Speed & Supports up to 8 Lines VoIP Phone & Device 8 lines, 4 SIP counts, 4 XML programmable context-sensitive soft keys Dual switched, auto-sensing gigabit ports, built-in poe, USB port 32 digitally programmable and customizable blf/speed-dial keys Built-in Bluetooth for syncing headsets and mobile devices for contact books, calendars & call transferring HD audio on the Handset and speakerphone; full duplex speakerphone